Structure of Color Filters
As the basic structure of the color filter, red (R), green (G) and blue (B) color resist patterns that allow transmission of light are formed on a thin glass substrate first, together with a black matrix that prevents defects such as light leakage while displaying black color as well as any color mixture with an adjacent color resist.
Then, an ITO (transparent conductive layer), which becomes the common electrode for a TFT array substrate, is formed over it.
When you look at the liquid crystal display from oblique angle, sometimes screen looks dark, color image being altered, or certain types of colors are not being recognized. Large-scale monitor requiring large visual line movement, or big screen watched people from different positions require a wide view-angle.
Many efforts have been made to obtain the display with wide view-angle.
- TN (Twisted Nematic) Technology
Standard type utilized in PC products, etc. Structure is simple but brightness or color image changes depending on a view-angle.
- VA (Vertical Alignment) Technology
VA Ribs are deposited on both color filter and TFT array sides to turn liquid crystal molecules in different directions and widen the view-angle.
- IPS (In-Plane-Switching) Technology
Two electrodes are deposited on the array side to rotate liquid crystal molecules horizontally to obtain wide view-angle.